The present invention relates generally to a printed circuit board and a method for manufacturing the same, and more particularly to a printed circuit board having conductive members and a method for manufacturing the same.
The recent design trend in integrated circuit chips is miniaturization. As the size of an integrated circuit chip is decreased the integration level of an integrated circuit chip increases accordingly, and therefore the number of circuits that can be located on a chip is increased as well. This increase in the number of circuits that can be located on a chip means that an increased number of signals can be inputted to and outputted from the integrated circuit chip. Therefore, due to this miniaturization, it is necessary to locate an increased number of input and output pins within a limited area of a semiconductor package.
A ball grid array (BGA) package has been developed and used to provide an increased number of input and output pins within a limited area of a semiconductor package. The BGA package uses mounting technology that employs a printed circuit board having high mounting density and high precision so that an increased number of parts, (i.e., semiconductor chips) can be mounted.
In order provide light, compact and slim electronic appliances, techniques for finely forming parts are required, and a printed circuit board for enabling high density mounting of parts must be provided.
In general, a printed circuit board includes line patterns made of a conductive material, such as copper, which are formed on an insulation layer immediately before mounting electronic parts. More specifically, a printed circuit board includes an insulation layer, metal lines, which are formed on surfaces of the insulation layer, and via metal lines, which are formed through the insulation layer so as to electrically connect the metal lines formed different surfaces of the insulation layer.
Conventional lead frame package include input and output pins that are one-dimensionally arranged along the edges of a chip. In contrast to the conventional lead frame package, in the BGA package solder balls are used as input and output pins. The solder balls are arranged two-dimensionally on a surface of a chip, and as such, pins can be located more efficiently than in the conventional lead frame package. Hence, in a printed circuit board to be used in a package such as the BGA package, ball lands should be necessarily formed on the surfaces thereof in order to attach solder balls.
In BGA packages, which use printed circuit boards having ball lands, slight modifications are made to the design of a BGA package in order to make similar printed circuit boards using the same or similar semiconductor chips.
However, in the conventional BGA packages, it may be difficult to manufacture a printed circuit board by bonding solder balls in conformity with the kinds of various packages on the same printed circuit board.
For example, in the case of a flip chip BGA package, which includes bumps for connecting bonding pads on a semiconductor chip with a printed circuit board in one-to-one correspondence, a slight design change may be possible by partially removing portions of the bumps.
Nevertheless, in the flip chip BGA package, the potential for design change is quite limited, and limitations necessarily exist in moving circuit lines connected between solder balls and bumps or changing the circuit lines by selectively connecting solder balls connected with various respective different signals to one bonding pad.
That is to say, a design change of circuit lines by selectively bonding solder balls connected with respective different signals to one ball land in conformity with the types of respective desired packages may be impossible to perform on the same printed circuit board.
Accordingly, even though printed circuit boards having basically the same design of circuit lines are adopted for respective types of packages, in the conventional BGA packages, printed circuit boards suitable for the respective packages must be newly designed and manufactured. Due to this fact, when changing the design of a printed circuit board, masks for forming the newly designed circuit lines, etc. must also be manufactured.
Further, due to the limitations of the conventional BGA packages, small changes result in increased costs because the printed circuit board must be newly designed and the processing time is increased due to the required manufacture of the newly designed printed circuit board.